The 1999 Bridge Creek–Moore tornado was an extremely powerful F5tornado in which the highest wind speeds ever measured globally, 301 miles per hour (484 km/h), were recorded by a Doppler on Wheels (DOW) radar. The tornado devastated parts of Oklahoma City, Oklahoma, along with surrounding suburbs and towns on May 3, 1999. Throughout its 85-minute existence, the tornado covered 38 miles (61 km), destroying thousands of homes, killing 36 people (plus an additional five indirectly), and leaving $1 billion in damage,[1] ranking it as the fifth-costliest on record, not accounting for inflation.[2]

The tornado first touched down at 6:23 p.m. CDT in Grady County, roughly 2 mi (3.2 km) south-southwest of Amber. It quickly intensified into a violent F4, and gradually reached F5 status after traveling 6.5 miles (10.5 km), at which time it struck the community of Bridge Creek. Once it moved through Bridge Creek, it fluctuated in strength from ranging from F2 to F5 status before it crossed into Cleveland County. Not long after entering the county, it reached F5 intensity for a third time as it moved through the city of Moore. By 7:30 p.m. CDT, the tornado crossed into Oklahoma County and battered southeastern Oklahoma City, Del City, and Midwest City before dissipating around 7:48 p.m. CDT just outside of Midwest City. In terms of structural losses, a total of 8,132 homes, 1,041 apartments, 260 businesses, 11 public buildings and seven churches were damaged or destroyed.

In the wake of the tornado, large-scale search and rescue operations took place in the affected areas. A major disaster declaration was signed by PresidentBill Clinton the following day, allowing for the state to receive federal aid. In the following months, disaster aid amounted to $67.8 million. In light of the fatalities that occurred under highway overpasses, the notion of them being safe areas was dismissed, and they were from then on considered to be one of the most dangerous places to be during a tornado. Reconstruction projects in the years following led to a safer, tornado-ready community. In May 2013, similar areas were again devastated by an EF5 tornado, but there were fewer fatalities despite structural damage similar in severity to the 1999 event.

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A map of the meteorological setup of the 1999 Oklahoma tornado outbreak. The map displays surface and upper level atmospheric features associated with the outbreak.

The Bridge Creek–Moore tornado was part of a much larger outbreak, which spawned 71 tornadoes across five states on May 3 alone.[3] On the morning of May 3, the Storm Prediction Center (SPC) issued a slight risk for severe weather later that day, as a dry line that stretched from western Kansas into western Texas approached a warm, humid air-mass over the Central Plains. Although cirrus clouds were present through much of the day, an eventual clearing allowed for the sun to heat up the moisture-laden region, creating significant atmospheric instability. By 7:00 a.m. CDT, CAPE values began exceeding 4,000 j/kg, a level which climatologically favors the development of severe thunderstorms.[4] This prompted the SPC to upgrade the forecasted threat of severe weather to a moderate risk for much of central Oklahoma.[5]

By the early afternoon hours, forecasters at both the SPC and the National Weather Service Weather Forecast Office in Norman, Oklahoma realized that a major event was likely to take place.[6] Conditions became highly conducive for tornadic development by 1:00 p.m. CDT as wind shear intensified over the region, creating a highly unstable atmosphere.[4] At 3:49 p.m. CDT, a high risk of severe weather was issued by the Storm Prediction Center for much of central Oklahoma.[7] Within minutes of this, the SPC issued a tornado watch for southern Kansas and the central two-thirds of Oklahoma just as supercells began developing over southwestern Oklahoma, prompting the issuance of a severe thunderstorm warning by 4:15 p.m. CDT.[4]

The thunderstorm that eventually spawned the F5 Bridge Creek–Moore tornado formed around 3:30 p.m. CDT over Tillman County. Tracking northeast, the storm strengthened and entered Comanche County shortly after 4:00 p.m. CDT.[8] There, hail up to 1.75 inches (44 mm) in diameter fell;[3] at 4:51 p.m. CDT, the first of 14 tornadoes associated with supercell "A" (the National Weather Service Weather Forecast Office in Norman designated lettered names for the three tornado-producing supercells in the outbreak in storm surveys) touched down along U.S. Route 62. Five more tornadoes touched down as the storm continued northeast; the sixth touchdown was an F3, which caused substantial damage in Grady County. At 6:23 p.m. CDT, the ninth tornado associated with supercell "A" touched down about 2 miles (3.2 km) south-southwest of Amber.[8]

That tornado quickly intensified as it crossed Oklahoma State Highway 92, attaining F4 strength about 4 miles (6.4 km) east-northeast of Amber. Damage consistent with this rating was sustained over the following 6.5 miles (10.5 km) before striking Bridge Creek. There, it attained the highest-possible rating on the Fujita Scale, F5. Damage in this area was extreme, as many homes were completely swept away, leaving only concrete slabs where the structures once were. Damage surveyors noted that the remaining structural debris from some of the homes in this area was finely granulated into small fragments, and that trees and shrubs were completely debarked.[9] A few of these homes were bolted to their foundations. Extensive ground scouring occurred, and vehicles were thrown hundreds of yards from where they originated, including a mangled pickup truck that was found wrapped around a telephone pole. It was in this area that a mobile Doppler weather Radar recorded winds of 301 mph (484 km/h) within the tornado, the highest wind speed ever recorded on earth.[10] However, since the record for maximum winds are reported from only non-tornadic events, the 253 mph (407 km/h) wind gust from Cyclone Olivia in 1996 retained the title.[11][12] About 1 inch (25 mm) of asphalt was scoured off of a road in this area by the violent tornado. Approximately 200 mobile homes/houses were destroyed, and hundreds of other structures were damaged. The Ridgecrest Baptist Church in Bridge Creek was also destroyed. Twelve persons died in Bridge Creek, nine in mobile homes, and all fatalities and the majority of injuries were concentrated in the Willow Lake Addition, Southern Hills Addition, and Bridge Creek Estates, consisting mostly of mobile homes. 39 people were injured in the area as well.[12][13] Continuing northeastward, the tornado briefly weakened to F4 status before becoming an F5 again as it neared the Grady-McClain County line, where a car was thrown roughly 0.25 mi (0.40 km), and a well-built home with anchor bolts was reduced to a bare slab.[12] At this time, it had attained a width of 1 mile (1.6 km).[8] Around 6:57 p.m. CDT, the National Weather Service Weather Forecast Office in Norman issued the first-ever tornado emergency for southern portions of the Oklahoma City metropolitan area.[14][15]

F5 damage to a house in Bridge Creek, with severe debarking and ground scouring visible on the property.

Paralleling Interstate 44, the tornado moved into McClain County, where it crossed the highway twice at F4 intensity, killing a woman as she was blown out from an underpass where she was attempting to seek shelter.[12] At 7:10 p.m. CDT, a satellite tornado touched down over an open field north of Newcastle; it was rated as an F0 due to lack of damage. Thirty-eight homes and 2 businesses were destroyed in McClain County, and 40 homes were damaged. Some of the homes were leveled at F4 intensity, and 17 people were injured.[12] After crossing the Canadian River, the tornado entered Cleveland County and weakened to F2 intensity. By this time, it had entered the southern reaches of the Oklahoma City limits. Several minutes after entering the county, it re-attained F4 status, and then moved directly into the city of Moore, where the tornado reached F5 intensity for a third time. Some of the most severe damage took place in Cleveland County, especially in the city of Moore, where 11 people were killed and 293 others were injured. The tornado caused an estimated $450 million in damage across the county. The first area impacted in Moore was the Country Place Estates subdivision, where 50 homes were damaged and one was completely swept away at F5 intensity, with only the foundation remaining. Several vehicles were picked up and tossed nearly 0.25 mi (0.40 km). According to local police, an airplane wing, believed to have been from an airport in Grady County, was found near Country Place Estates. Next, the powerful tornado struck the densely populated Eastlake Estates at F5 intensity, killing three people and reducing entire rows of homes to rubble. In one instance, four adjacent homes were completely destroyed, with only concrete slabs remaining, warranting an F5 rating at that location. Three other homes in this housing division also received F5 damage, with the remaining destruction rated high-end F4. Severe debarking of trees was noted in this area. At the Emerald Springs Apartments, three more people were killed and a two-story apartment building was mostly flattened.[3]

Just outside the Eastlake Estates, an awards ceremony at Westmoore High School was being held at the time of the tornado; however, adequate warning time allowed those at the school to seek shelter and no injures took place at the awards ceremony. Ultimately, Westmoore High sustained heavy damage and dozens of cars in the parking lot were tossed around, many of which were destroyed. The tornado proceeded through additional densely populated areas of Moore shortly thereafter, where several large groups of homes were flattened in residential areas, with a mixture of high-end F4 and low-end F5 damage noted. Near Janeway Avenue, four people were killed in an area where multiple homes were completely destroyed. A woman was also killed when she was blown out from under the Shields overpass of Interstate 35. The tornado weakened somewhat as it moved through the Highland Park neighborhood of Moore, but still caused widespread F3 and F4 damage.[3]

Approximate tracks of the supercells during the outbreak. The supercell which spawned the F5 tornado is marked "A" in green.

An American flag blows in the wind next to the remains of a home destroyed by the tornado

The tornado then entered Oklahoma County and struck the southeast fringes of Oklahoma City, where it re-intensified to high-end F4 strength and two people were killed as a trucking company was completely destroyed. Numerous industrial buildings were leveled in this area. A freight car, weighing 36,000 lb (16,000 kg) was thrown 0.75 mi (1.21 km). The car bounced as it traveled, remaining airborne for 50 to 100 yd (46 to 91 m) at a time. Multiple homes were also completely destroyed in southwest Oklahoma City, and one woman was killed in that area. Crossing SE 44th into Del City, the tornado moved through the highly populated Del Aire housing addition, killing 6 persons and damaging or destroying hundreds of homes, with many sustaining F3 to F4 damage.[3] Seven people were killed as a direct result of the tornado in Del City, and hundreds of homes were damaged or destroyed.[16] The tornado then crossed Sooner Rd., damaged an entry gate and several buildings at Tinker Air Force Base, then crossed 29th St. into Midwest City, destroying 1 building at the Boeing Complex and damaging 2 others. Widespread F3/F4 damage continued as the tornado moved across Interstate 40 affecting a large business district. Approximately 800 vehicles were damaged at Hudiburg Auto Group, located just south of Interstate 40. Hundreds of the vehicles were moved from their original location, and dozens of vehicles were picked up and tossed northward across Interstate 40 into several motels, a distance of approximately 2 tenths of a mile. Numerous motels and other businesses including Hampton Inn, Comfort Inn, Inn Suites, Clarion Inn, Cracker Barrel, and portions of Rose State College, were destroyed. Some of the damage through this area was rated high-end F4, however low-end F5 was considered. The tornado then continued into another residential area located between SE 15th and Reno Ave, where 3 fatalities occurred. High F4 damage was inflicted to 4 homes in this area. Two of these homes were located between SE 12th and SE 11th, near Buena Vista, and the other 2 homes were located on Will Rogers Rd. just south of SE 15th. Damage then diminished rapidly to F0/F1 strength as the tornado crossed Reno Ave. before dissipating 3 blocks north of Reno Ave. between Sooner Rd. and Air Depot Blvd. Throughout Oklahoma County, 12 people were killed and 234 others were injured while losses amounted to $450 million.[3]

Throughout the tornado's path, 36 people were killed as a direct result of the storm and five more died of indirect causes in the hours following it. According to the Oklahoma Department of Health, an estimated 583 people were injured by the tornado, accounting for those who likely did not go to the hospital or were unaccounted for.[8] In terms of structural losses, a total of 8,132 homes, 1,041 apartments, 260 businesses, 11 public buildings and seven churches were damaged or destroyed.[17]

Continuing search and rescue efforts for 13 people who were listed as missing through May 7 were assisted by urban search and rescue dogs from across the country.[21] Nearly 1,000 members of the Oklahoma National Guard were deployed throughout the affected region. The American Red Cross had set up ten mobile feeding stations by this time and stated that 30 more were en route.[22] On May 8, a disaster recovery center was opened in Moore for individuals recovering from the tornadoes.[23] According to the Army Corps of Engineers, roughly 500,000 cubic yards (382,277 cubic meters) of debris was left behind and would likely take weeks to clear.[24] Within the first few days of the disaster declaration, relief funds began being sent to families who requested aid. By May 9, roughly $180,000 had been approved by FEMA for disaster housing assistance.[25]

Residents search for belongings in the remains of their homes.

Debris removal finally began on May 12 as seven cleanup teams were sent to the region, more were expected to join over the following days.[26] That day, FEMA also declared that seven counties, Canadian, Craig, Grady, Lincoln, Logan, Noble and Oklahoma, were eligible for federal financial assistance.[27] By May 13, roughly $1.6 million in disaster funds had been approved for housing and businesses loans.[28] This quickly rose to more than $5.9 million over the following five days.[29] By May 21, more than 3,000 volunteers from across the country traveled to Oklahoma to help residents recover; 1,000 of these volunteers were sent to Bridge Creek to clean up debris, cut trees, sort donations and cook meals.[30] With a $452,199 grant from FEMA, a 60-day outreach program for victims suffering tornado-related stress was set up to help them cope with trauma.[31]

Applications for federal aid continued through June, with state approvals reaching $54 million on June 3. By this date, the Army Corps of Engineers reported that 964,170 cubic yards (737,160 cubic meters), roughly 58%, of the 1.65 million cubic yards (1.26 million cubic meters) of debris had been removed.[32] Assistance for farmers and ranchers who suffered severe losses from the tornadoes was also available by June 3.[33] After more than a month of being open, emergency shelters were set to be closed on June 18.[34] On June 21, an educational road show made by FEMA visited the hardest hit areas in Oklahoma to urge residents to build storm cellars.[35] According to FEMA, more than 9,500 residents applied for federal aid during the allocated period in the wake of the tornadoes. Most of the applicants lived in Oklahoma and Cleveland counties, 3,800 and 3,757 persons respectively. In all, disaster recovery aid for the tornadoes amounted to roughly $67.8 million by the end of July 2.[36]

Aerial view of one of the overpasses under which one person was killed by the tornado.

From a meteorological and safety standpoint, the tornado also brought the use of highway overpasses as shelters into question. Prior to the events on May 3, 1999, videos of people taking shelter in overpasses during tornadoes in the past (most notably one filmed during the April 26, 1991 tornado outbreak involving a television news crew and other bystanders) gave the public misunderstanding that overpasses provided shelter from tornadoes. For nearly 20 years, meteorologists had questioned the safety of these structures; however, they lacked incidents involving loss of life.[37] During the May 3 outbreak, three overpasses were directly struck by tornadoes, with a fatality taking place at each one. Two of these were from the F5 Bridge Creek–Moore tornado while the third was from a small, F2 which struck a rural area north of Oklahoma City.[38] According to a study by the National Oceanic and Atmospheric Administration, seeking shelter in an overpass "is to become a stationary target for flying debris."[39]

Over the following four years, a $12 million project to construct storm shelters for residents across Oklahoma City was enacted. The goal was to create a safer community in a tornado-prone region. By May 2003, a total of 6,016 safe rooms were constructed. On May 9, 2003, the new initiative was put to the test as a tornado outbreak in the region spawned an F4 tornado, which took a path similar to that of the Bridge Creek–Moore tornado. Due to the higher standards for public safety, no one was killed by the 2003 tornado, a substantial improvement in just four years.[40] On May 20, 2013, an EF5 tornado took a roughly similar path to the 1999 storm, tracking through the heart of Moore. Throughout the city, 24 people were killed (+1 indirectly) and more than 230 were injured.[41][42]

1. These are the unadjusted damage totals in millions of US dollars.
2. Raw damage totals adjusted for inflation, in millions of 2015 USD.
3. A search of NCDC Storm Data indicates no tornadoes between 1999 and 2010 have caused more than $400 million in damage.